169 
botanist will hardly doubt that the genera comprehended under the name of 
' Incompletae are in reality of a lower degree of organization than Polypetalae ; 
and the student need be under no alarai about the difficulty that may appear 
j to be connected wdth these anomalies and exceptions, for after a very little ex- 
perience he will be scarcely conscious of their existence. 
I Incompletae are connected with Polypetalse most immediately by way of 
' Lauraceae and Myristicaceae, or Empetraceae and Euphorbiaceae ; Chloranthaceae 
probably join them with Gnetaceous Gymnosperms ; and Menispermaceae 
certainly constitute a passage to Smilaceous Endogens, as Aristolochiaceae 
, possibly do to Araceae. 
The sub -class separates naturally into the five following groups. 
1 . EectembrgO0ae» Calyx very imperfect. Embryo straight. 
I 2. ac|)IamHtlO0ae* Calyx and corolla altogether absent. 
3. ^ubiferO0ae* Calyx tubular, often resembling a corolla (and with some 
of the characters of the other groups). 
4. ®olumno 0 ae 4 Stamens monadelphous, and ovary many- (six)- celled ; or, 
at all events, the latter character combined with an 
epigynous flower. 
5. CurhembrHO0ac* Embryo curved round mealy albumen; or having the 
form of a horse- shoe ; or spiral ; (calyx rarely tubular). 
The attention of botanists requires to be especially called to this part of the 
class of Exogens. In consequence of the species being little cultivated, and 
uninviting in appearance, they have been much neglected ; but there can be no 
doubt that a careful investigation of the large numbers of unarranged and un- 
determined Incomplete or Apetalous plants which now encumber every her- 
barium of much extent would place the limits of the following orders in a 
much clearer light, and richly rew^ard the industry of the botanist who should 
have energy enough to undertake, and skill enough to execute, the very diffi- 
cult task of putting them in order. 
Group I. I^ectembrpojpse. 
Essential Character. — Calyx exceedingly imperfect, very often only rudimentary, 
ragged, and more a shapeless membrane than a calyx ; sometimes more regular. Embryo 
straight, either with or without albumen. 
If it were not for the Datiscal alliance, which is the least developed form 
of this group, Rectembryosse would be nearly the same as the old Amentace^, 
except that a part is stationed in the Salical alliance of Achlamydosae. The 
genera consist chiefly of trees with inconspicuous flowers, many of which are 
arranged in catkins. The group can only be confounded with Curvembryosse, 
and they are usually herbaceous plants, their flowers are never in catkins, and 
their calyx is far more completely developed than in this group ; to say 
nothing of the distinction in their curved embryo. 
Alliance I. AMENTALES, 
Essential Character. — Flowers in catkins. Carpels always 2 or more, combined 
into a solid pistil. All Trees or arborescent shrubs. 
Tlie syncarpous nature of their ovaries divides these from every other 
